The use of ocular inserts of various shapes for treating eye disorders is known. For example, the patent to Katz, U.S. Pat. No. 4,343,787, describes the use of a water-soluble polymer to make a device which is inserted under the lower lid of the eye for treating dry eye syndrome. It is said that it can be of any shape and size and, preferably, is in the shape of a rod, doughnut, oval or quarter moon. It can be so large as to cover the entire globe of the eye.
Another ocular insert is suggested by the patent to Ness, U.S. Pat. No. 3,618,604. This is a generally crescent-shaped small article which fits under the lower lid and is used for dispersing drugs to the eye. Still other such articles of various shapes are disclosed in U.S. Pat. Nos. 3,995,635; 3,867,519; 3,828,777; 3,854,480; 4,571,039; 4,484,922; and 4,592,752.
While these disclosed devices may find use for certain purposes, each of them has one or more drawbacks which are particularly related to their shapes. For example, several of the devices are so large that they obscure the vision. Others which are small enough to fit under the lower lid and not obscure the vision, are of non-symmetrical shape and are difficult to place in the eye, perhaps requiring the use of a special implement for placing the device in the eye. Others are uncomfortable to wear. Still others are difficult to retain in the eye and demonstrate a high rate of dislodgement.